# Help on my masters thesis please!

#### xDafonso

##### New Member
So i'm a dentistry student working on my masters thesis and i find myself needing some help on some statistical analysis. I'm (trying) to use SPSS and my experience on mathmatics/statistic is close to none at all.
So i have a group of 80 samples (of a suture material) which are divided in 4 groups depending on size (80 total, 4 groups of 20). I performed a experiment and the outcome for each suture is yes/no depending on what happened.
Using SPSS i inserted the data using two Variables: - the first represents the size, there are 4 groups of sizes so 4 values: 1=1mm, 2=2mm, 3=3mm and 4=5mm. As there are 20 samples per group there are 20 specimens with the value 1, 20 with value 2, 20 with value 3 and 20 with value 5. - the second represents wether or not an event took place after the experiment.
It goes something like this:
(variable 1) (variable 2)
1 No
1 No
1 Yes
(20 times)
.....
2 No
2 No
2 Yes
(20 times)
3 No
3 No
3 Yes
........
4 No
4 No
4 No
........

The event occurs on 55% (11) sutures in group 1, 25% (5) in group 2 and 15% (3) on groups 3 and 4. I'm trying to determine wether there is a relation between the size of the sutures and the outcome, for instance, group one has the smaller sutures of only 1mm so the event will happen more often compared to the others.
Is there any analysis that will give me this results? I'm pretty sure this is very basic but, as i said, my experience in these matters is rather small =P
If i didnt make myselft clear in something please question me, and i would really appreciate any help!

Last edited:

#### Dason

I stopped reading when I saw you were a dentist. We don't take kindly to dentists here. Especially non-american dentists. Amirite victor?

#### xDafonso

##### New Member
Is that so? Did you have some bad experiences or something?
And it's actually Afonso, Dason, but close enough i guess. =P

#### StilloftheNight

##### New Member
I stopped reading when I saw you were a dentist. We don't take kindly to dentists here. Especially non-american dentists. Amirite victor?
lol why is that? I am not a dentist or a dental student by the way!

#### Karabiner

##### TS Contributor
I'm trying to determine wether there is a relation between the size of the sutures and the outcome, for instance, group one has the smaller sutures of only 1mm so the event will happen more often compared to the others.
Crosstabulation (4x2 table) with Chi² test could be used.

With kind regards

K.

#### xDafonso

##### New Member
Thanks a lot Karabiner, i think that did the trick